Recruiting

Phase 2

FG-3246A Study of FG-3246 in Participants With Metastatic Castration-Resistant Prostate Cancer (mCRPC)

Sponsor:

Kyntra Bio

Code:

NCT06842498

Conditions

Metastatic Castration-Resistant Prostate Cancer

Eligibility Criteria

Sex: Male

Age: 18+

Healthy Volunteers: Not accepted

Interventions

FG-3246

Study Details

Brief summary:

The purpose of this study is to evaluate the safety, efficacy, tolerability, and pharmacokinetics (PK) of FG-3246, a cluster of differentiation 46 (CD46) targeting antibody-drug conjugate (ADC), in the treatment of participants with mCRPC who have progressed following treatment with one prior second-generation androgen receptor signaling inhibitor (ARSI) in any setting and no prior taxane therapy in the mCRPC setting.

Conditions

Metastatic Castration-Resistant Prostate Cancer

Study ID

NCT06842498

Start date

Feb 22, 2026

Status verified date

Aug, 2026

Completion date

Mar 31, 2028

Anticipated

Primary completion date

Mar 31, 2028

Anticipated

Eligibility Criteria

Sex: Male

Age: 18+

Healthy Volunteers: Not accepted

Key Inclusion Criteria:

Participant must have histological, and/or cytological confirmation of prostate adenocarcinoma on all prior tumor biopsies.
Participant with soft tissue disease and a safely accessible soft tissue tumor lesion(s) must agree to biopsy of a primary or metastatic lesion during screening. Alternatively, participant may provide a suitable archival biopsy of a primary or metastatic lesion.
Participant must have serum testosterone levels <50 nanograms (ng)/deciliter (dL) during screening.
Participant is required to have progressed on no more than one prior treatment with a second generation ARSI (abiraterone acetate, enzalutamide, apalutamide, or darolutamide) initiated in either the castration-sensitive or castration-resistant setting.
Participant must have progressive mCRPC following last treatment at screening.
Participant must have ≥1 metastatic lesion that is present on baseline Computed Tomography (CT), Magnetic Resonance Imaging (MRI), or bone scan obtained ≤28 days prior to randomization.
Participant must have adequate organ function during screening.

Key Exclusion Criteria:

Participant has received previous treatment with a therapeutic targeting CD46.
Participant has small cell neuroendocrine carcinoma (pure or mixed) on any prior histologic evaluation of primary or metastatic lesion.
Participant has progressed on more than one prior second-generation ARSI in any setting or has received more than two prior second-generation ARSIs in any setting.
Participants must not have received recent anticancer treatments before enrollment. Ongoing supportive or hormonal therapies are allowed if they were started well before randomization and are continued without change.
Participant has received any prior radiation therapy within 14 days prior to randomization.
Participant has a known actionable mutation or gene alteration, for example, BRCA1 mutation, for which approved therapies are available, for example, PARP inhibitors, unless these therapies are not appropriate for the participant as determined by the investigator or the participant refuses such therapy.
Participant has National Cancer institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) ≥Grade 2 peripheral neuropathy at the time of screening from any etiology.
Participant has received any prior chemotherapy; however, one prior taxane-based chemotherapy in the castration-sensitive setting is allowed if completed >12 months before randomization.
Participant has known hypersensitivity to the components of FG-3246 or its analogs or a history of allergic or anaphylactic reaction to human, humanized, or chimeric monoclonal antibodies.
Participant has diagnosis with any other malignancy in the past 5 years, except for adequately treated basal cell or squamous cell carcinoma of the skin.
Participant requires treatment with a strong cytochrome P450 3A4 (CYP3A4) inhibitor or inducer drug that cannot be safely discontinued.

NOTE: Other protocol-defined inclusion/exclusion may apply.

Study Design

Enrollment

75 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: FG-3246 1.8 mg/kg

Participants will receive FG-3246 1.8 milligrams (mg)/kilogram (kg) administered via intravenous (IV) infusion on Day 1 of each 21-day treatment cycle (every 3 weeks \[Q3W\]) until radiographic progression, unacceptable safety and tolerability, participant or investigator decision to stop treatment, other withdrawal criteria are met, or sponsor decision to close the study.

experimental: FG-3246 2.4 mg/kg

Participants will receive FG-3246 2.4 mg/kg administered via IV infusion on Day 1 of each 21-day treatment cycle (Q3W) until radiographic progression, unacceptable safety and tolerability, participant or investigator decision to stop treatment, other withdrawal criteria are met, or sponsor decision to close the study.

experimental: FG-3246 2.7 mg/kg

Participants will receive FG-3246 2.7 mg/kg administered via IV infusion on Day 1 of each 21-day treatment cycle (Q3W) until radiographic progression, unacceptable safety and tolerability, participant or investigator decision to stop treatment, other withdrawal criteria are met, or sponsor decision to close the study.

Interventions

FG-3246

FG-3246 will be administered per schedule specified in the arm description.

Primary outcome measure

Radiographic Progression-free Survival (rPFS) By Investigator Assessment Per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 and Prostate Cancer Clinical Trials Working Group 3 (PCWG3) Criteria [ Time Frame: Until radiographic progression is noted (up to approximately 25 months) ]
Number of Participants With Treatment-emergent Adverse Events (TEAEs) [ Time Frame: From first dose until 28 days after last dose (up to approximately 25 months) ]
Maximum Plasma Concentration (Cmax) of FG-3246, Total Anti-cluster of Differentiation 46 Antibody (CD46), and Free Monomethyl Auristatin E (MMAE) [ Time Frame: Within each 21 day treatment cycle from Cycle 1 through 28 days post last dose (up to approximately 25 months) ]

Central Contacts and Locations

Central contacts

Javier Moreno

415-978-1466 jmoreno@kyntrabio.com

Mairead Carney

415-978-1337 mcarney@kyntrabio.com

Locations

Western Regional Medical Center - City of Hope Phoenix Goodyear

Recruiting

Goodyear, Arizona, United States, 85338

Contacts

Firas Shada

847-342-6910 fshadad@coh.org

HonorHealth Research Institute

Recruiting

Scottsdale, Arizona, United States, 85258

Contacts

Amy Malensek

480-323-1791 amalensek@honorhealth.com

The University of Arizona Cancer Center - North Campus

Recruiting

Tucson, Arizona, United States, 85719

Contacts

Alana Sudkamp

520-621-5895 alanamsudkamp@arizona.edu

VA Greater Los Angeles Healthcare System

Recruiting

Los Angeles, California, United States, 90073

Contacts

Matthew Rettig

310-478-3711 matthew.rettig@va.gov

UCLA Clark Urology Center

Recruiting

Los Angeles, California, United States, 90095

Contacts

Ankush Sachdeva

310-794-3452 asachdeva@mednet.ucla.edu

University of California San Francisco

Recruiting

San Francisco, California, United States, 94158

Contacts

Daniel Avins

415-514-4222 daniel.avins@ucsf.edu

New Haven Hospital - Yale Cancer Center

Recruiting

New Haven, Connecticut, United States, 06519

Contacts

Amanda Davis

475-321-7899 Amanda.Davis@yale.edu

Bioresearch Partner - Aventura

Recruiting

Aventura, Florida, United States, 33180

Contacts

Angelo Gousse

833-489-4968 agoussemd@bioresearchpartner.com

Bioresearch Partner - Hialeah

Recruiting

Hialeah, Florida, United States, 33013

Contacts

Luis Rangel

833-489-4968 lrangel@bioresearchpartner.com

Biogenix Molecular, LLC

Recruiting

Miami, Florida, United States, 33165

Contacts

Jerry Joseph

786-791-1799 jjoseph@cira-health.com

Winship Cancer Institute, Emory University

Recruiting

Atlanta, Georgia, United States, 30322

Contacts

Emily Setser

404-778-4968 emily.setser@emory.edu

East Jefferson General Hospital Metairie

Recruiting

New Orleans, Louisiana, United States, 70112

Contacts

Sarah Bigelow

504-988-6123 sbigelow@tulane.edu

New Mexico Oncology Hematology Consultants, Ltd.

Recruiting

Albuquerque, New Mexico, United States, 87109

Contacts

Daisy Sanchez

505-842-8171 research@nmohc.com

Duke University Medical Center - Duke Cancer Center

Recruiting

Durham, North Carolina, United States, 27710

Contacts

Andrew Armstrong

919-668-4667 andrew.armstrong@duke.edu

University Hospitals Cleveland Medical Center

Recruiting

Cleveland, Ohio, United States, 44106

Contacts

Pedro Barata

801-585-0255 Pedro.Barata@UHhospitals.org

Carolina Urologic Research Center

Recruiting

Myrtle Beach, South Carolina, United States, 29572

Contacts

Kate Valipour

843-449-1010 kate.valipour@startresearch.com

Henry-Joyce Cancer Clinic

Recruiting

Nashville, Tennessee, United States, 37232

Contacts

Clinical Trials Office, Vanderbilt-Ingram Cancer Center

800-811-8480 CIP@VUMC.ORG

University of Texas Southwestern Medical Center

Recruiting

Dallas, Texas, United States, 75390

Contacts

Amy Rowell

214-645-9688 amy.rowell@utsouthwestern.edu

Oncology Consultants

Recruiting

Houston, Texas, United States, 77030

Contacts

Julio Peguero

713-600-0900 jpeguero@oncologyconsultants.com

University of Virginia Comprehensive Cancer Center

Recruiting

Charlottesville, Virginia, United States, 22908

Contacts

Clinical Trials Navigator

434-982-0539 uvacancertrials@hscmail.mcc.virginia.edu

Fred Hutchinson Cancer Center

Recruiting

Seattle, Washington, United States, 98109

Contacts

Michael Schweizer

206-606-6252 schweize@uw.edu

University of Washington Medical Center

Recruiting

Seattle, Washington, United States, 98195

Contacts

Michael Schweizer

206-606-6252 schweize@uw.edu

Northwest Medical Specialties, PLLC - Tacoma

Recruiting

Tacoma, Washington, United States, 98405

Contacts

Patricia Walsh

253-428-8700 pwalsh@nwmsonline.com

More Information

Sponsor

Kyntra Bio

Last update posted

Aug 17, 2026

Last verified

Aug, 2026

Keywords

FG-3246
FOR46
mCRPC
CRPC
CD46
Prostate cancer
Antibody-drug conjugate
Metastatic prostate cancer
FibroGen
ADC
Kyntra
Kyntra Bio
KYNB

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by Kyntra Bio on 2026-08-17.